Google and Facebook, between them, employ somewhere in the range of 15,000-20,000 engineers. Look at the entirety of the two companies' web presence (ie their jQuery hacker designed stuff) - that's work that could be done by a very small percentage of those 15,000 people.
The real challenge for both those companies is scalability and algorithmic complexity. They both do things like tweak well-established open source packages, implement machine learning, build programming languages/operating systems, influence technical web standards, etc. Stuff that decidedly is NOT the realm of your average hacker who decided to skip college because the curriculum wasn't "revelant".
If you don't believe me, feel free to try to get hired at either company without a college degree. Unless you've done something VERY notable, it's not gonna happen.